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Shipud writes "A recent article in Journal of Biomolecular structure and Dynamicsproposes to define life by semantic voting [Note: open-access article]: 'The definitions of life are more than often in conflict with one another. Undeniably, however, most of them do have a point, one or another or several, and common sense suggests that, probably, one could arrive to a consensus, if only the authors, some two centuries apart from one another, could be brought together. One thing, however, can be done – short of voting in absentia – asking which terms in the definitions are the most frequent and, thus, perhaps, reflecting the most important points shared by many.' The author arrives at a six-word definition, as explained here."

because the passive aggressive culture we have today needs it in order to feel secure. it loves argumentum ad populum (among others).

Most insightful comment I've seen in ages.

The need to distinguish life from non-life arises from the need to define will, which human society sorely needs in order to find stable footing in the void left by religion. It's a hopeless endeavor, as we witness in the article, since will is but a bunch of norms. There is no rigid barrier between "things that act by themselves" (conventionally animals, God, but not zombies) and "things that are devoid of motive". It ultimately boils down to where the norms of the physical universe (laws of physics) come from. This is a problem posed by materialism. Biology, being materialistic, can never have an opinion on this.

What Biology is actually is doing, is trying to define its boundaries. Re-phrase it like that and all is fine.

The definition I like came from NASA astrobio asking the question, what would be an observable indication of life on a remote planet. That what might exist in spectra, or surface photos or any remote observation that would be a hallmark of life.

One definition promoted by David Wolpert was the notion of self dissimilarity across scales. Consider that perfectly organized things (crystals) and perfectly disorganized things (gas) are both dead. So a hallmark of life is not entropy. Gas and crystals are dead because as you zoom out on them, their organizational simmilarity does not change (seen a small region of gas or a small region of a crystal, and you can extrapolate or predict all properties of the organization at a larger scale.). On the otherhand life has organizations that change as you zoom out. atoms become become proteins, become complexes, become organelles, become single cells. Single cells become organs. Organs organize into animals. Animals organize into packs. Different kinds of animals form an eco system. And so on.

At each scale, the organization observed remains predictable for a while as you zoom then it abruptly shifts to a new one. The idea is that a hallmark of life is that if you look how each scale can be predicted from the scales below it, that this predictcablilty, perhaps measured as information surprisal, is nearly constant over a range, and then abruptly goes to zero at some scale.

You should therefore look for this same scaling phenomena in spectra or sand dunes or whatever you can remotely observe. A planet that displays anomolies in this probably has some sort of activity that is partially organizing it.